It is often desirable to impart to textile articles certain functional attributes. For example, while textile articles formed from some synthetic polymeric materials (e.g., polyarylene sulfides) are themselves flame resistant, there is a continual need to improve the flame retardant properties thereof. Imparting flame-retardant attributes to synthetic filaments and fibers can typically be accomplished by incorporating an appropriate flame-retardant material physically or chemically within the polymeric material prior to being formed into a textile article and/or to apply an appropriate functional component topically to the textile article by treating the textile article in a post-production step. The present invention relates to the latter technique for imparting flame-retardant attributes to textile articles, namely by the topical application of particulate flame-retardant materials adhered or bound to the surface thereof.
One of the main difficulties with current fibers in textiles, whether they are natural (e.g. cotton) or synthetic (polyester, nylon) is that they readily burn. To preserve lives and property, it is critical to reduce the flammability of textiles. Most flame retardants in use today are added as fillers or contain halogens. Fillers can reduce the physical properties of the clothing, and are not bound to the fiber. Halogenated flame retardants have environmental concerns as well as release highly toxic gases during combustion. New non-halogenated flame retardants with minimal environmental impact and improved physical properties are needed for textiles.
Recently, U.S. Pat. No. 6,607,994 to Soane et al (the entire content of which is expressly incorporated hereinto by reference) has disclosed nanoparticle-based permanent treatments for textiles. More particularly, an agent or other payload is disclosed therein as being surrounded by or contained within a polymeric encapsulator that is reactive to webs to give textile reactive nanoparticles. As best as applicants can determine there is no disclosure therein of employing superabsorbent polymeric (SAP) particles as the encapsulator and/or modification of the SAP particles to achieve bonding to a textile article.
U.S. Pat. No. 6,290,887 to Sheu et al (the entire content of which is expressly incorporated hereinto by reference), superabsorbent polymer (SAP) particles pre-loaded with moisture have been incorporated into a thermoplastic polymer (e.g., polyethylene) so as to obtain a SAP-enriched plastics material that may be extruded into desired shapes (e.g., as an outer jacket of a telecommunications cable).
It would therefore be desirable if flame-retardant SAP could be associated with textile articles so as to impart flame-retardant properties thereto. It is toward providing fulfilling such a need that the present invention is directed.
Broadly, the present invention is embodied in textile articles and processes of making the same whereby flame-retardant SAP particles are associated with textile articles so as to impart flame-retardant properties to the thereto. The SAP particles are most preferably hydrated with an aqueous flame-retardant solution. In this regard, the flame-retardant solution may consist essentially of water alone or a water solution containing one or more water soluble inorganic flame retardants.
When SAP particles are hydrated with an aqueous inorganic flame retardant solution, the SAP particles may thereafter be dried to remove substantially the water component. In such a manner, the inorganic flame retardant will remain as a dried residue physically entrained within the SAP particles. As such, the SAP particles serve as a physical matrix in which the inorganic flame retardant is homogenously dispersed. The SAP particles may then be blended with a synthetic resin as is or alternatively may be ground into more finely divided particles which contain the dried residue of the aqueous inorganic flame retardant solution and then blended with a suitable synthetic resin.
These and other aspects and advantages will become more apparent after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.